| 1. |
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| 2. |
- Chasman, Daniel I., et al.
(författare)
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Integration of genome-wide association studies with biological knowledge identifies six novel genes related to kidney function
- 2012
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Ingår i: Human Molecular Genetics. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 21:24, s. 5329-5343
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Tidskriftsartikel (refereegranskat)abstract
- In conducting genome-wide association studies (GWAS), analytical approaches leveraging biological information may further understanding of the pathophysiology of clinical traits. To discover novel associations with estimated glomerular filtration rate (eGFR), a measure of kidney function, we developed a strategy for integrating prior biological knowledge into the existing GWAS data for eGFR from the CKDGen Consortium. Our strategy focuses on single nucleotide polymorphism (SNPs) in genes that are connected by functional evidence, determined by literature mining and gene ontology (GO) hierarchies, to genes near previously validated eGFR associations. It then requires association thresholds consistent with multiple testing, and finally evaluates novel candidates by independent replication. Among the samples of European ancestry, we identified a genome-wide significant SNP in FBXL20 (P 5.6 10(9)) in meta-analysis of all available data, and additional SNPs at the INHBC, LRP2, PLEKHA1, SLC3A2 and SLC7A6 genes meeting multiple-testing corrected significance for replication and overall P-values of 4.5 10(4)2.2 10(7). Neither the novel PLEKHA1 nor FBXL20 associations, both further supported by association with eGFR among African Americans and with transcript abundance, would have been implicated by eGFR candidate gene approaches. LRP2, encoding the megalin receptor, was identified through connection with the previously known eGFR gene DAB2 and extends understanding of the megalin system in kidney function. These findings highlight integration of existing genome-wide association data with independent biological knowledge to uncover novel candidate eGFR associations, including candidates lacking known connections to kidney-specific pathways. The strategy may also be applicable to other clinical phenotypes, although more testing will be needed to assess its potential for discovery in general.
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| 3. |
- Koettgen, Anna, et al.
(författare)
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Genome-wide association analyses identify 18 new loci associated with serum urate concentrations
- 2013
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 45:2, s. 145-154
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Tidskriftsartikel (refereegranskat)abstract
- Elevated serum urate concentrations can cause gout, a prevalent and painful inflammatory arthritis. By combining data from >140,000 individuals of European ancestry within the Global Urate Genetics Consortium (GUGC), we identified and replicated 28 genome-wide significant loci in association with serum urate concentrations (18 new regions in or near TRIM46, INHBB, SEMBT1, TMEM171, VEGFA, BAZ1B, PRKAG2, STC1, HNF4G, A1CF, ATXN2, UBE2Q2, IGF1R, NFAT5, MAF, HLF, ACVR1B-ACVRL1 and B3GNT4). Associations for many of the loci were of similar magnitude in individuals of non-European ancestry. We further characterized these loci for associations with gout, transcript expression and the fractional excretion of urate. Network analyses implicate the inhibins-activins signaling pathways and glucose metabolism in systemic urate control. New candidate genes for serum urate concentration highlight the importance of metabolic control of urate production and excretion, which may have implications for the treatment and prevention of gout.
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| 4. |
- Pattaro, Cristian, et al.
(författare)
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Genome-Wide Association and Functional Follow-Up Reveals New Loci for Kidney Function
- 2012
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Ingår i: PLoS Genetics. - : Public Library of Science (PLoS). - 1553-7390 .- 1553-7404. ; 8:3, s. e1002584-
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Tidskriftsartikel (refereegranskat)abstract
- Chronic kidney disease (CKD) is an important public health problem with a genetic component. We performed genomewide association studies in up to 130,600 European ancestry participants overall, and stratified for key CKD risk factors. We uncovered 6 new loci in association with estimated glomerular filtration rate (eGFR), the primary clinical measure of CKD, in or near MPPED2, DDX1, SLC47A1, CDK12, CASP9, and INO80. Morpholino knockdown of mpped2 and casp9 in zebrafish embryos revealed podocyte and tubular abnormalities with altered dextran clearance, suggesting a role for these genes in renal function. By providing new insights into genes that regulate renal function, these results could further our understanding of the pathogenesis of CKD.
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| 5. |
- A, Teschendorff, et al.
(författare)
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The dynamics of DNA methylation covariation patterns in carcinogenesis
- 2014
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Ingår i: PLoS Computational Biology. - : Public Library of Science (PLoS). - 1553-734X .- 1553-7358. ; 10:7
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Tidskriftsartikel (refereegranskat)abstract
- Recently it has been observed that cancer tissue is characterised by an increased variability in DNA methylation patterns. However, how the correlative patterns in genome-wide DNA methylation change during the carcinogenic progress has not yet been explored. Here we study genome-wide inter-CpG correlations in DNA methylation, in addition to single site variability, during cervical carcinogenesis. We demonstrate how the study of changes in DNA methylation covariation patterns across normal, intra-epithelial neoplasia and invasive cancer allows the identification of CpG sites that indicate the risk of neoplastic transformation in stages prior to neoplasia. Importantly, we show that the covariation in DNA methylation at these risk CpG loci is maximal immediately prior to the onset of cancer, supporting the view that high epigenetic diversity in normal cells increases the risk of cancer. Consistent with this, we observe that invasive cancers exhibit increased covariation in DNA methylation at the risk CpG sites relative to normal tissue, but lower levels relative to pre-cancerous lesions. We further show that the identified risk CpG sites undergo preferential DNA methylation changes in relation to human papilloma virus infection and age. Results are validated in independent data including prospectively collected samples prior to neoplastic transformation. Our data are consistent with a phase transition model of carcinogenesis, in which epigenetic diversity is maximal prior to the onset of cancer. The model and algorithm proposed here may allow, in future, network biomarkers predicting the risk of neoplastic transformation to be identified.
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| 6. |
- Abelev, Betty, et al.
(författare)
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Measurement of prompt J/psi and beauty hadron production cross sections at mid-rapidity in pp collisions at root s=7 TeV
- 2012
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Ingår i: Journal of High Energy Physics. - 1029-8479. ; :11
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Tidskriftsartikel (refereegranskat)abstract
- The ALICE experiment at the LHC has studied J/psi production at mid-rapidity in pp collisions at root s = 7 TeV through its electron pair decay on a data sample corresponding to an integrated luminosity L-int = 5.6 nb(-1). The fraction of J/psi from the decay of long-lived beauty hadrons was determined for J/psi candidates with transverse momentum p(t) > 1,3 GeV/c and rapidity vertical bar y vertical bar < 0.9. The cross section for prompt J/psi mesons, i.e. directly produced J/psi and prompt decays of heavier charmonium states such as the psi(2S) and chi(c) resonances, is sigma(prompt J/psi) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 8.3 +/- 0.8(stat.) +/- 1.1 (syst.)(-1.4)(+1.5) (syst. pol.) mu b. The cross section for the production of b-hadrons decaying to J/psi with p(t) > 1.3 GeV/c and vertical bar y vertical bar < 0.9 is a sigma(J/psi <- hB) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 1.46 +/- 0.38 (stat.)(-0.32)(+0.26) (syst.) mu b. The results are compared to QCD model predictions. The shape of the p(t) and y distributions of b-quarks predicted by perturbative QCD model calculations are used to extrapolate the measured cross section to derive the b (b) over bar pair total cross section and d sigma/dy at mid-rapidity.
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| 7. |
- Abelev, Betty, et al.
(författare)
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Underlying Event measurements in pp collisions at root s=0.9 and 7 TeV with the ALICE experiment at the LHC
- 2012
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Ingår i: Journal of High Energy Physics. - 1029-8479. ; :7
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Tidskriftsartikel (refereegranskat)abstract
- We present measurements of Underlying Event observables in pp collisions at root s = 0 : 9 and 7 TeV. The analysis is performed as a function of the highest charged-particle transverse momentum p(T),L-T in the event. Different regions are defined with respect to the azimuthal direction of the leading (highest transverse momentum) track: Toward, Transverse and Away. The Toward and Away regions collect the fragmentation products of the hardest partonic interaction. The Transverse region is expected to be most sensitive to the Underlying Event activity. The study is performed with charged particles above three different p(T) thresholds: 0.15, 0.5 and 1.0 GeV/c. In the Transverse region we observe an increase in the multiplicity of a factor 2-3 between the lower and higher collision energies, depending on the track p(T) threshold considered. Data are compared to PYTHIA 6.4, PYTHIA 8.1 and PHOJET. On average, all models considered underestimate the multiplicity and summed p(T) in the Transverse region by about 10-30%.
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| 8. |
- Aronsson, Helena, et al.
(författare)
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Effects of pig and dairy slurry application on N and P leaching from crop rotations with spring cereals and forage leys
- 2014
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Ingår i: Nutrient cycling in agroecosystems. - : Springer Science and Business Media LLC. - 1385-1314 .- 1573-0867. ; 98, s. 281-293
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Tidskriftsartikel (refereegranskat)abstract
- Two crop rotations dominated by spring cereals and grass/clover leys on a clay soil were studied over 2 years with respect to nitrogen (N) and phosphorus (P) leaching associated with pig or dairy slurry application in April, June and October. Leaching losses of total N (TN), total P (TP), nitrate-N and dissolved reactive P (DRP) were determined in separately tile-drained field plots (four replicates). Mean annual DRP leaching after October application of dairy slurry (17 kg P ha(-1)) to growing grass/clover was 0.37 kg ha(-1). It was significantly higher than after October application of pig slurry (13 kg ha(-1)) following spring cereals (0.16 kg ha(-1)) and than in the unfertilised control (0.07 kg P ha(-1)). The proportion of DRP in TP in drainage water from the grass/clover crop rotation (35 %) was higher than from the spring cereal rotation (25 %) and the control (14 %). The grass/clover rotation proved to be very robust with respect to N leaching, with mean TN leaching of 10.5 kg ha(-1) year(-1) compared with 19.2 kg ha(-1) year(-1) from the cereal crop rotation. Pig slurry application after cereals in October resulted in TN leaching of 25.7 kg ha(-1) compared with 7.0 kg ha(-1) year(-1) after application to grass/clover in October and 19.1 kg ha(-1) year(-1) after application to spring cereals in April. In conclusion, these results show that crop rotations dominated by forage leys need special attention with respect to DRP leaching and that slurry application should be avoided during wet conditions or combined with methods to increase adsorption of P to soil particles.
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| 9. |
- Aronsson, Helena, et al.
(författare)
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N and P losses from two crop rotations on a clay soil with applications of liquid manure
- 2011
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Ingår i: NJF Report. - 1653-2015. ; 7, s. 102-105
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- In Sweden, nitrogen (N) and phosphorus (P) leaching losses and mitigation strategies for cropping systems using liquid manure have been studied on sandy soils, e.g. at Mellby experimental field in southern Sweden (Halmstad, 7.2 oC and 803 mm) (Torstensson & Aronsson, 2000). In 2008, a corresponding experiment was established on a clay soil in a neighbouring field (Lilla Böslid; 30% clay) in order to enable estimations of leaching and recommendations relating to the use of pig and cattle slurry for clay soils in this region. The field consists of 36 separately tile-drained plots with flow-proportional water sampling for estimations of nutrient leaching. Two crop rotations, representing pig and dairy production, are being studied, including control plots (Table 1). The main objectives of the studies, which started in 2010, are to: 1) quantify P leaching from this soil, 2) determine how N and P leaching is affected by time of slurry application to different crops (with and without incorporation) and 3) identify possibilities for improving N and P use efficiency on farms with intensive livestock production. Transport of dissolved dinitrous oxide in drainage water is also being measured in a connected project together with Halmstad University. The study is being funded by the Swedish Farmers' Foundation for Agricultural Research.
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| 10. |
- Canovic, Sead, 1979, et al.
(författare)
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Microstructural Investigation of the Initial Oxidation of the FeCrAlRE Alloy Kanthal AF in Dry and Wet O-2 at 600 and 800 degrees C
- 2010
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Ingår i: Journal of the Electrochemical Society. - : The Electrochemical Society. - 1945-7111 .- 0013-4651. ; 157:6, s. C223-C230
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Tidskriftsartikel (refereegranskat)abstract
- The FeCrAlRE (where RE is reactive element) alloy Kanthal AF was exposed isothermally at 600 and 800 degrees C for 72 h in dry O-2 and in O-2 with 10 vol % H2O. The mass gains were 3-5 times higher at the higher temperature. The presence of water vapor increased the oxidation rate at 800 degrees C, while no significant effect was observed at 600 degrees C. A thin two-layered oxide formed at 600 degrees C: an outer (Fe, Cr)(2)O-3 corundum-type oxide, containing some Al, and an inner, probably amorphous, Al-rich oxide. At 800 degrees C a two-layered oxide formed in both environments. The inner layer consisted of inward grown alpha-Al2O3. In dry O-2 the originally formed outward grown gamma-Al2O3 had transformed to alpha-Al2O3 after 72 h. Water vapor stabilized the outward grown gamma-Al2O3 and hence no transformation occurred after 72 h in humid environment. RE-rich oxide particles with varying composition (Y, Zr, and Ti) were distributed in the base oxide at both temperatures and in both environments. The RE-rich particles were separated from the alloy substrate by a layer of Al-rich oxide. At 800 degrees C the Y-rich RE particles were surrounded by thick oxide patches in both dry and humid O-2.
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| 11. |
- Canovic, Sead, et al.
(författare)
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Microstructural investigation of the initial oxidation of the FeCrAlRE alloy Kanthal AF in dry and wet O2 at 600 and 800°C
- 2010
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Ingår i: Journal of the Electrochemical Society. - : The electrochemical society. - 0013-4651 .- 1945-7111. ; 157:6, s. C223-C230
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Tidskriftsartikel (refereegranskat)abstract
- The FeCrAlRE (where RE is reactive element) alloy Kanthal AF was exposed isothermally at 600 and 800°C for 72 h in dry O2 and in O2 with 10 vol % H2O. The mass gains were 3–5 times higher at the higher temperature. The presence of water vapor increased the oxidation rate at 800°C, while no significant effect was observed at 600°C. A thin two-layered oxide formed at 600°C: an outer (Fe,Cr)2O3 corundum-type oxide, containing some Al, and an inner, probably amorphous, Al-rich oxide. At 800°C a two-layered oxide formed in both environments. The inner layer consisted of inward grown a-Al2O3. In dry O2 the originally formed outward grown g-Al2O3 had transformed to a-Al2O3 after 72 h. Water vapor stabilized the outward grown g-Al2O3 and hence no transformation occurred after 72 h in humid environment. RE-rich oxide particles with varying composition (Y, Zr, and Ti) were distributed in the base oxide at both temperatures and in both environments. The RE-rich particles were separated from the alloy substrate by a layer of Al-rich oxide. At 800°C the Y-rich RE particles were surrounded by thick oxide patches in both dry and humid O2.
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| 12. |
- Köttgen, Anna, et al.
(författare)
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New loci associated with kidney function and chronic kidney disease
- 2010
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 42:5, s. 376-384
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Tidskriftsartikel (refereegranskat)abstract
- Chronic kidney disease (CKD) is a significant public health problem, and recent genetic studies have identified common CKD susceptibility variants. The CKDGen consortium performed a meta-analysis of genome-wide association data in 67,093 individuals of European ancestry from 20 predominantly population-based studies in order to identify new susceptibility loci for reduced renal function as estimated by serum creatinine (eGFRcrea), serum cystatin c (eGFRcys) and CKD (eGFRcrea < 60 ml/min/1.73 m2; n = 5,807 individuals with CKD (cases)). Follow-up of the 23 new genome-wide–significant loci (P < 5 × 10−8) in 22,982 replication samples identified 13 new loci affecting renal function and CKD (in or near LASS2, GCKR, ALMS1, TFDP2, DAB2, SLC34A1, VEGFA, PRKAG2, PIP5K1B, ATXN2, DACH1, UBE2Q2 and SLC7A9) and 7 loci suspected to affect creatinine production and secretion (CPS1, SLC22A2, TMEM60, WDR37, SLC6A13, WDR72 and BCAS3). These results further our understanding of the biologic mechanisms of kidney function by identifying loci that potentially influence nephrogenesis, podocyte function, angiogenesis, solute transport and metabolic functions of the kidney.
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| 13. |
- Liu, Fang, 1975, et al.
(författare)
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TEM Investigation of the Microstructure of the Scale Formed on a FeCrAlRE Alloy at 900 A degrees C: The Effect of Y-rich RE Particles
- 2010
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Ingår i: Oxidation of Metals. - : Springer Science and Business Media LLC. - 1573-4889 .- 0030-770X. ; 74:1-2, s. 11-32
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Tidskriftsartikel (refereegranskat)abstract
- Three oxide features: the thin and smooth protective oxide, reactive element (Ti-, Zr- or Y-rich) particles, and patches of thick oxide surrounding the Y-rich reactive element particles, were observed on a commercial FeCrAlRE alloy, Kanthal AF, exposed at 900 A degrees C. The microstructural development of the patches of thick oxide was investigated on samples exposed for 24 or 168 h in either dry O-2 or O-2 + 40% H2O. Analytical transmission electron microscopy in combination with site-precision TEM sample preparation by FIB/SEM was used. In all patches a thin but continuous inward growing alpha-Al2O3 layer was formed under a thick outward growing alumina layer, which initially consisted only of gamma-Al2O3. In dry O-2, transformation of gamma-Al2O3 (in the outer layer) to alpha-Al2O3 had started during 24 h and a considerable amount of gamma-Al2O3 had transformed after 168 h. The transformation originated immediately above the inward growing alpha-Al2O3. No such transformation occurred in O-2 + H2O. The possible effects of the Y-rich RE particles, as well as the effects of water vapour, on the oxidation were discussed.
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| 14. |
- Liu, Jian, et al.
(författare)
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Assessment of phosphorus (P) leaching losses from a long-term manured sandy soil
- 2012
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Long-term repeated applications of animal manure at high rates contribute to build-up of soil phosphorus (P) status, which poses a risk of P losses by leaching. However, soil characteristics such as P sorption capacity and degree of P saturation can greatly affect P leaching in certain circumstances. Phosphorus leaching was studied in a long-term experimental field with a sandy soil in southwest Sweden. Field measurements, model simulations, and laboratory lysimeters, were used to assess the risk of P leaching associated with pig slurry applications. The field plots received different P applications resulting in average annual P surpluses of 11-24 kg ha-1 during 1983-2009. Mean annual total-P leaching and total-P concentration measured at a drain depth of 90 cm were in general low, ranging respectively from 0.14 kg ha-1 and 0.06 mg L-1 at the high rate of slurry application to 0.20 kg ha-1 and 0.08 mg L-1 in the mineral P treatment. The simulations with the ICECREAM model confirmed that the abundant P sorption capacity due to considerable Fe, Al, and Ca present in the soil overshadowed the effects of soil P status and fertilization. Laboratory lysimeter studies showed high potential of P leaching from the top-soil due to long-term pig slurry applications even long before the field experiment started. The conclusion is that P sorption capacity of the sub-soil should also be considered, besides soil P status and fertilization, when identifying hotspots and designing P mitigation strategies.
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| 15. |
- Liu, Jian, et al.
(författare)
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Catch crops to mitigate phosphorus leaching under cold climate
- 2012
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Nutrient leaching from agricultural land contributes greatly to the eutrophication of recipient water bodies. Catch crops (cover crops) used for reducing nitrogen leaching are proposed to mitigate phosphorus (P) leaching too. However, in regions with winter frost, catch crops may act as a source of P losses after plant cell lysis. A field study on two clay soils in south Sweden in 2009-2012 examined eight potential P catch crops; chicory (Cichorium intybus L.), cocksfoot (Dactylis glomerata L.), perennial ryegrass (Lolium perenne L.), red clover (Trifolium pretense L.), phacelia (Phacelia tanacetifolia L.), white mustard (Sinapis alba L.), and radish (Raphanus sativus L.) with the latter represented by both R. oleiformis and R. longipinnatus. Soil columns with catch crops and controls were collected in late autumn and used in leaching experiments. The columns were undergone seven repeated freezing-thawing cycles (FTCs) in the laboratory and irrigated with 70 mm simulated rainfall both before and after FTCs. The P content in leachate was analyzed after each irrigation. Leaching of total-P increased after FTCs compared with before (p=0.045) and varied significantly with year (p<0.0001) and species (p=0.037). Chicory and white mustard had lower total-P leaching than the control, while radish (R. oleiformis) and red clover had highest total-P leaching of all species. Ryegrass and radish (R. oleiformis) were the most sensitive species to frost in terms of causing the largest increase in total-P concentrations compared with the control. Radish (R. longipinnatus), cocksfoot, and chicory were the least sensitive crops and caused no significant increase in P leaching after FTCs. It was concluded that the effect of catch crops on P leaching differs between years and that perennial ryegrass, commonly grown as a catch crop in the Nordic countries, tends to leach more P than other potential catch crops after exposure to severe frost.
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| 16. |
- Liu, Jian, et al.
(författare)
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Freezing-thawing effects on phosphorus leaching from catch crops
- 2014
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Ingår i: Nutrient cycling in agroecosystems. - : Springer Science and Business Media LLC. - 1385-1314 .- 1573-0867. ; 99, s. 17-30
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Tidskriftsartikel (refereegranskat)abstract
- It is suggested that catch crops can be grown to reduce phosphorus (P) losses. However, after exposure to freezing-thawing cycles (FTCs), catch crop material can become a source of P losses to waters in moderately cold climates. This study screened potential P leaching from intact plant material of eight catch crop species: chicory (Chichorium intybus L.), cocksfoot (Dactylis glomerata L.), perennial ryegrass (Lolium perenne L.), red clover (Trifolium pratense L.), phacelia (Phacelia tanacetifolia L.), white mustard (Sinapis alba L.), oilseed radish (Raphanus sativus L. oleiformis), and white radish (R. longipinnatus). The catch crops were grown in six field experiments on clay soils, where soil lysimeters (0.25 m deep) with intact crops were extracted in autumn and after used for leaching experiments before and after seven FTCs in the laboratory. The eight catch crops did not reduce P leaching before FTCs. After FTCs, leachate total-P concentration from ryegrass, oilseed radish and red clover lysimeters were significantly (p=0.0022) higher than those from the other species and the control without a catch crop. FTCS significantly (p= 0.0064) altered total-P concentration and the proportions of different forms of P. There was a significant increase in total-P concentration in leachate from ryegrass (p=0.0008) and oilseed radish (p= 0.02). Thus, the potential risk of P leaching from ryegrass and oilseed radish material after FTCs must ne considered, since they are commonly grown as nitrogen catch crops in the Nordic countries. Morever, the roots of the tested catch crops contained 7-86 % total-P, which is important when ealuating O leaching risks.
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| 17. |
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| 18. |
- Liu, Jian, et al.
(författare)
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Long-term measurements and model simulations of phosphorus leaching from a manured sandy soil
- 2012
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Ingår i: Journal of Soil and Water Conservation. - 0022-4561. ; 67, s. 101-110
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Tidskriftsartikel (refereegranskat)abstract
- Cropping systems with high phosphorus (P) inputs may constitute a risk of P leaching, which contributes to eutrophication. This study was to identify P leaching risks associated with three long-term fertilization regimes in separately tile-drained plots on a sandy soil in southwest Sweden. The three regimes resulted in different annual P surpluses of, on average: 16 kg P ha-1 (14 lb P ac-1) in mineral form, and 18 kg P ha-1 (16 lb P ac-1) and 37 kg P ha-1 (33 lb P ac-1) as pig slurry. The importance of different soil characteristics (soil P, iron, aluminum, and calcium content, and degree of P saturation (DPS)) and processes (water flow and P sorption/desorption) was examined using 15 years (1989 to 2003) of P leaching measurements and simulations with the ICECREAM model. Measurements of high soil P content and DPS values in the topsoil, in combination with high precipitation and rapid water flow, indicated a high potential for P losses, which was confirmed by the model simulations. However, the model considerably overestimated total-P leaching by a factor of 5 to 9, since measured P leaching was small for all treatments. Measured mean annual total-P leaching and total-P concentration ranged respectively from 0.14 kg ha-1 (0.12 lb ac-1) and 0.06 mg L-1 at a high rate of slurry application to 0.20 kg ha-1 (0.18 lb ac-1) and 0.08 mg L-1 in the mineral P treatment. The differences in concentration were statistically significant (p < 0.001). A main conclusion from this 15-year study was that annual pig slurry application rates of 37 to 58 kg P ha-1 (33 to 52 lb P ac-1) did not increase P leaching. High sorption capacity of the subsoil, caused by Fe, Al, and Ca, was obviously very important for controlling P losses. Thus, information on soil P content and fertilization must be supplemented with estimates of soil P sorption capacity when evaluating the risk of P leaching for different soils. This must also be considered in models used for assessment of P leaching from arable land. The current ICECREAM model does not include appropriate functions for describing P sorption/desorption processes in this type of soil and needs further development.
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| 19. |
- Liu, Jian, et al.
(författare)
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Phosphorus leaching from a clay and sandy soil supplied with manure and mineral fertilizer
- 2012
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Phosphorus (P) leaching from agricultural fields contributes to eutrophication of adjacent water bodies. The complexity among factors controlling P leaching losses requires careful consideration in designing effective mitigation strategies. We studied P leaching (both total-P and dissolved reactive P) from lysimeters filled with clay or sandy topsoil before and after addition of 30 kg P ha-1 in the laboratory. The clay lysimeters were collected from a field with separately tile-drained plots and the results were compared with data from that field. The topsoils were treated with different sources of P (pig slurry or mineral P), which were either surface applied or incorporated into the soil. The initial total-P concentrations in lysimeter leachate were lower from the clay soil (0.13 mg L-1) than from the sandy soil (0.21 mg L-1), but in the clay soil they increased considerably after slurry application, to 1.39 mg L-1 for incorporated slurry and 2.76 mg L-1 for surface-applied slurry. The field study on the clay soil confirmed that surface-applied slurry increases P leaching under certain conditions. Critical events in the crop rotation were application in autumn on the soil surface, after cereals or on grass/clover, while spring application did not increase P leaching. Thus time of application and incorporation of slurry after application may be important for reducing P losses from clay soils.
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| 20. |
- Liu, Jian, et al.
(författare)
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Phosphorus leaching from loamy sand and clay loam topsoils after application of pig slurry
- 2012
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Ingår i: SpringerPlus. - : Springer Science and Business Media LLC. - 2193-1801. ; 1, s. 1-10
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Tidskriftsartikel (refereegranskat)abstract
- Management of animal waste is essential for guaranteeing good water quality. A laboratory leaching study with intact soil columns was performed to investigate the risk of phosphorus (P) leaching from a clay loam and a loamy sand. The columns (0.2 m deep) were irrigated before and after application of pig slurry on the surface or after incorporation, or application of mineral P, each at a rate of 30 kg P ha-1. The two soils had different initial P contents (i.e. the ammonium lactate-extractable P was 65 and 142 mg kg-1 for the clay loam and loamy sand, respectively), but had similar P sorption characteristics (P sorption index 3.0) and degree of P saturation (17-21%). Concentrations of dissolved reactive P (DRP) and total P (TP) before P application were significantly higher in leachate from the loamy sand (TP 0.21 mg L-1) than from the clay loam (TP 0.13 mg L-1), but only increased significantly after P application to the clay loam. The highest concentrations were found when slurry was surface-applied (DRP 1.77 mg L-1), while incorporation decreased the DRP concentration by 64% in the clay loam. Thus moderate slurry application to a sandy soil with low P saturation did not pose a major risk of P leaching. However, application of P increased the risk of P leaching from the clay loam, irrespective of application method and despite low P saturation. The results show the importance of considering soil texture and structure in addition to soil chemical characteristics in risk assessments of P leaching. Structured soils such as the clay loam used in this study are high risk soils and application of P to bare soil during wet periods, e.g. in autumn or spring, should be followed by incorporation or avoided completely.
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| 21. |
- Liu, Jian, et al.
(författare)
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Phosphorus leaching risk assessments and measured losses from a long-term manured sandy soil
- 2011
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Ingår i: NJF Report. - 1653-2015. ; 7, s. 30-33
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Long-term repeated applications of animal manure at high rates contribute to buildup of soil P status, which poses a risk of P losses by leaching. However, contrary phenomenon may present in soils with abundant P sorption capacities, which brings difficulties in assessing the risk of P leaching. Phosphorus leaching was studied in a long-term experimental field with a sandy soil in southwest Sweden. Field measurements, model simulations, and laboratory lysimeter experiments, were used to assess the risk of P leaching associated with pig slurry applications. The plots in the field received different P applications, i.e. high rate of P (58 kg P ha-1 yr-1) with pig slurry, low rate of P (37 kg P ha-1 yr-1) with pig slurry, and mineral P (24 kg P ha-1 yr-1) without N applications, since the experiment started in 1983. These treatments resulted in average annual surpluses of P from 16 kg ha-1 to 37 kg ha-1. Mean annual total-P leaching and total-P concentration measured at a drain depth of 90 cm ranged respectively from 0.14 kg ha-1 and 0.06 mg L-1 at the high rate of slurry application to 0.20 kg ha-1 and 0.08 mg L-1 in the mineral P treatment. These observations were in general low in a Swedish context and pig slurry application did not elevate P concentrations in drainage water. One explanation was that the abundant P sorption capacity due to considerable Fe, Al, and Ca present in the soil overshadowed the effects of soil P status and fertilization. It was confirmed by the simulations with the ICECREAM model, where the role of the soil P pool for leaching was tested. The model produced 5 to 9 times higher P leaching than measured when no special attention was paid to the high sorption capacity. Laboratory lysimeter studies showed high potential of P leaching from the topsoils in this field, which was resulted from long-term pig slurry applications even long before the field experiment started. This was consistent with the results with model simulations with the low P sorption capacity. On one hand, although high amount of P leaching has not been observed, this field has a high risk of P leaching if pig slurry application continues to saturate the soil P sorption capacity; on the other hand, it indicated that the subsoil played a crucial role in sorbing P moving through the soil profile and reducing P concentrations in drainage. One main conclusion from the study was that soil P sorption capacity should also be considered, besides soil P status and fertilization, when identifying hotspots and designing P mitigation strategies.
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| 22. |
- Liu, Jian, et al.
(författare)
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Potential phosphorus leaching from sandy topsoils with different fertilizer histories before and after application of pig slurry
- 2012
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Ingår i: Soil Use and Management. - : Wiley. - 0266-0032 .- 1475-2743. ; 28, s. 457-467
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Tidskriftsartikel (refereegranskat)abstract
- This study investigated the effects of historical long-term and recent single applications of pig slurry on P leaching from intact columns of two sandy topsoils (Mellby and Böslid). The soils had similar physical properties, but different soil P status (ammonium lactate-extractable P; P-AL) and degree of P saturation (DPS-AL). Mellby had P-AL of 220-280 mg kg-1 and DPS-AL of 32-42%, which was higher than for Böslid (P-AL 140 mg kg-1 and DPS 21%). The study investigated the effects since 1983 of four treatments with different fertilizer histories, in summary high (HighSlurryMellby) and low (LowSlurryMellby) rates of pig slurry and mineral P (MinMellby) applications at Mellby and mineral P application at Böslid (MinBöslid). The columns were irrigated in the laboratory five times before and five times after a single application of pig slurry (22 kg P ha-1). Concentrations of dissolved reactive P (DRP), dissolved organic P and total-P (TP) in leachate and loads were significantly higher (p <0.005) from the treatments at Mellby than those at Böslid. TP concentrations followed the trend: HighSlurryMellby (0.57-0.59 mg L-1) > MinMellby (0.41-0.49 mg L-1) > LowSlurryMellby (0.31-0.36 mg L-1) > MinBöslid (0.14-0.15 mg L-1), both before and after the single slurry application. DRP concentrations in leachate were positively correlated with DPS-AL values in the topsoil (R2=0.95, p<0.0001), and increased with greater DPS-AL values after the single slurry application (R2=0.79, p<0.0001). Thus, DPS-AL can be an appropriate indicator of P leaching risk from sandy soils. Moreover, the build-up of soil P due to long-term repeated manure applications seems to be more important for potential P losses than a single manure application.
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| 23. |
- Parsa, Afshin, et al.
(författare)
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Common Variants in Mendelian Kidney Disease Genes and Their Association with Renal Function
- 2013
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Ingår i: Journal of the American Society of Nephrology. - 1046-6673 .- 1533-3450. ; 24:12, s. 2105-2117
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Tidskriftsartikel (refereegranskat)abstract
- Many common genetic variants identified by genome-wide association studies for complex traits map to genes previously linked to rare inherited Mendelian disorders. A systematic analysis of common single-nucleotide polymorphisms (SNPs) in genes responsible for Mendelian diseases with kidney phenotypes has not been performed. We thus developed a comprehensive database of genes for Mendelian kidney conditions and evaluated the association between common genetic variants within these genes and kidney function in the general population. Using the Online Mendelian Inheritance in Man database, we identified 731 unique disease entries related to specific renal search terms and confirmed a kidney phenotype in 218 of these entries, corresponding to mutations in 258 genes. We interrogated common SNPs (minor allele frequency >5%) within these genes for association with the estimated GFR in 74,354 European-ancestry participants from the CKDGen Consortium. However, the top four candidate SNPs (rs6433115 at LRP2, rs1050700 at TSC1, rs249942 at PALB2, and rs9827843 at ROBO2) did not achieve significance in a stage 2 meta-analysis performed in 56,246 additional independent individuals, indicating that these common SNPs are not associated with estimated GFR. The effect of less common or rare variants in these genes on kidney function in the general population and disease-specific cohorts requires further research.
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| 24. |
- Schroeder, Julia, et al.
(författare)
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MicroRNA-138 is a potential regulator of memory performance in humans
- 2014
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Ingår i: Frontiers in Human Neuroscience. - : Frontiers Media SA. - 1662-5161. ; 8, s. 501-
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Tidskriftsartikel (refereegranskat)abstract
- Genetic factors underlie a substantial proportion of individual differences in cognitive functions in humans, including processes related to episodic and working memory. While genetic association studies have proposed several candidate memory genes, these currently explain only a minor fraction of the phenotypic variance. Here, we performed genome-wide screening on 13 episodic and working memory phenotypes in 1318 participants of the Berlin Aging Study II aged 60 years or older. The analyses highlight a number of novel single nucleotide polymorphisms (SNPs) associated with memory performance, including one located in a putative regulatory region of microRNA (miRNA) hsa-mir-138-5p (rs9882688, P-value = 7.8 x 10(-9)). Expression quantitative trait locus analyses on next-generation RNA-sequencing data revealed that rs9882688 genotypes show a significant correlation with the expression levels of this miRNA in 309 human lymphoblastoid cell lines (P-value = 5 x 10(-4)). In silico modeling of other top-ranking GWAS signals identified an additional memory-associated SNP in the 3' untranslated region (3' UTR) of DCP1B, a gene encoding a core component of the mRNA decapping complex in humans, predicted to interfere with hsa-mir-138-5p binding. This prediction was confirmed in vitro by luciferase assays showing differential binding of hsa-mir-138-5p to 3' UTR reporter constructs in two human cell lines (HEK293: P-value = 0.0470; SH-SY5Y: P-value = 0.0866). Finally, expression profiling of hsa-mir-138-5p and DCP1B mRNA in human post-mortem brain tissue revealed that both molecules are expressed simultaneously in frontal cortex and hippocampus, suggesting that the proposed interaction between hsa-mir-138-5p and DCP1B may also take place in vivo. In summary, by combining unbiased genome-wide screening with extensive in silico modeling, in vitro functional assays, and gene expression profiling, our study identified miRNA-138 as a potential molecular regulator of human memory function.
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